Sunday, 18 July 2010

I closed the last post with the line "If it doesn't work well, it doesn't matter who made it, it's still crap.", and coincidentally, this weeks mission was to reattach the side stand. If you've never owned a BMW Boxer (or at least a /7 age one) you may wonder why you normally see them parked on the centre stand. This is because while the BMW side stand is clearly to one side of the motorcycle, and therefore justifies that part of it's name, it's a little less clear as to how it came by the "stand" part of it's name. If you'll accept my definition of "crap", then "side crap" would be a better title for the thing.

The problem is that the side stand has been designed to meet some spurious regulation that assumes that the worst thing that can happen to you is pulling away with the side stand of your motorcycle extended. In their enthusiasm for making the stand idiot proof, BMW seem to have sacrificed it's ability to be gravity proof.

Since I'd already disposed of the centre stand mounts, then I was left with a choice between always parking near a wall, or improving on the side stand somewhat. I took a section of 1 1/2" OD, 1/8"wall tube and cut in half length ways to make a "saddle" to sit over the BMW's lower frame rail. Then I cut the original bracket at an angle so the stand would be further over centre when it reached the end of it's travel. My idea was that by increasing the amount the stand moved over centre, and by arranging for the motorcycle to lean over further, then things would be a lot less precarious while the thing was parked up.

The point of the "saddle" is three fold. Firstly, it's around 50% thicker than the factory frame rails, so welding it to the cast steel bracket is a lot easier, and welding the saddle to the frame doesn't present a problem either. Secondly, welding the saddle to the tube distributes the forces into the frame in a much happier fashion than welding the bracket directly to the frame rail. Thirdly, and possibly most importantly, two tacks on the inner most edge of the saddle will locate it firmly enough to support the weight of the motorcycle, allowing you to test out the positioning. Should it prove unsatisfactory, extending the stand and pushing down on it, will easily break the two tacks off.

Somewhere down the line, the original side stand bolt had gone missing and been replaced with a hex headed set screw that had had it's head ground to a countersink and a slot hacksawed in the end of it. That meant that the stand was pivoting on the thread of the screw, which isn't ideal, so I took an 8mm countersunk Allen bolt, and threaded it further up it's shank and cut the threaded portion off to the correct length. With that sorted out, I re-assembled the stand onto the modified bracket and got Ben to hold the bike at the angle I wanted it while I tacked the saddle to the frame. After a couple of goes at finding a position for it, I eventually had the stand positioned so that the motorcycle didn't appear to be in any danger of falling over, and the stand itself stowed away neatly missing the exhaust and gear change.

Many people would feel that was an inordinate amount of trouble to go to over a simple side stand, but I don't agree. Many of those same people would happily go to immense amounts of trouble, and expense, over a paint job. If the motorcycle is prone to committing Hari Kari every time it's left on the stand, how long is that paint job going to remain unmarked? Coming back to the motorcycle and finding that it has not only decided to lie down and have a rest, but also leaked the majority of the fuel that was in the tank all over the tarmac doesn't do much to improve your day either. I may have mentioned that it's not enough for a thing to work, it has to work well.

Something the motorcycle is clearly lacking, is a seat, and since the object of the exercise is to build something that makes the average passer-by think "Oh! Look! A Café Racer!" it needs a bum stop seat. I could just buy one, but there are a couple of snags with that, to whit, my knees and the point.

My knees would prefer it if the seating position was nearer to the standard height, and not the sort of height that an after market bum stop mounted on the seat rails would dictate. The point is that, at heart, this is a styling exercise and slapping some random piece of fiber glass on there doesn't contribute to a cohesive look. Now that it has a stand I can wheel the motorcycle out into the fresh air and stand back far enough from it to make some sort of a decision about what I want the seat to look like.

Because I need the seat height, I might as well stow a gel battery on its side under the seat, in which case, some of the other electrics might as well live there too. Hopefully I can stow the coils under the tank, I'm planning on dumping the standard electro-mechanical regulator and the diode board for the much more compact (and cheap) components from the inside a car alternator and there will probably be some trickery with relays involved. Unless I have some electronics made to do the same job...

The seat unit is going to be a bit problematic. It has to raise the seat height, provide for hiding some of the electrical bits, look like it belongs with the tank and at the same time it has to say "Cafe Racer" loudly enough to overcome a certain amount of handle bar prejudice that is sadly rampant in the population at large.

And it has to do all that well.

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